NASHVILLE, Tenn.--A German scientist who swam all 652 miles of the Tennessee River and studied it's water quality says he found "staggering levels of microplastic pollution" in the river.

Dr. Andreas Fath is a professor of medical and life sciences at Germany's Furtwangen University and has completed analysis of other rivers such as Germany's Rhine River.

According to Dr. Fath, samples collected in the Tennessee River contained concentrations of microplastics 8,000% higher than those he found in the Rhine River during testing in 2014. Fath adds levels were also 80% higher than in China's Yangtze River.

The results were so shocking to Fath, he says he and his team triple checked the results. Fath and his team believe the high levels are being caused by the decomposition of large plastic waste in landfills. In a statement released via the Tennessee Aquarium Conservation Institute, Fath says “Once the land is filled with plastic waste, it breaks up, step by step, with the help of microorganisms, ultraviolet light and mechanical forces. At the end of the day, the plastic is flushed into rivers as secondary microplastic.”

Dr. Martin Knoll, Professor of Geology and Hydrology at Sewanee: The University of the South, says the plastic waste can also be making it's way into the river by washing from roadsides through Tennessee's limestone then moving into the rivers.

Fath's study has garnered support from other Tennessee agencies, including Tennessee State Parks and the Tennessee Valley Authority.